pinnoite
noun
pin·no·ite
ˈpinəˌwīt
plural -s
: a hydrous magnesium borate Mg(BO2)2.3H2O usually occurring in yellow nodular masses with a radiating fibrous structure (hardness 3–4, specific gravity 2.3)
Word History
Etymology
German pinnoit, from Pinno, 19th century German mining official + German -it -ite